diff --git a/2020/10/main.php b/2020/10/main.php
new file mode 100644
index 0000000..9e18020
--- /dev/null
+++ b/2020/10/main.php
@@ -0,0 +1,42 @@
+<?php
+
+function diffs($jolts) {
+	sort($jolts);
+	array_unshift($jolts, 0);
+	$builtin = array_slice($jolts, -1)[0] + 3;
+	array_push($jolts, $builtin);
+
+	$c = array();
+	for ($i = 0; $i < count($jolts); $i++) {
+		$d = $jolts[$i+1] - $jolts[$i];
+		$c[$d]++;
+	}
+
+	return $c;
+}
+
+function totals($jolts) {
+	sort($jolts);
+
+	$c = array();
+	$c[0] = 1;
+	foreach ($jolts as $a) {
+		for ($i = 1; $i < 4; $i++)
+			$c[$a] += $c[$a-$i];
+	}
+	print_r($c);
+}
+
+$f = fopen("test.txt", "r");
+$jolts = array();
+while (!feof($f))
+	array_push($jolts, intval(fgets($f)));
+fclose($f);
+
+print_r($jolts);
+$c = diffs($jolts);
+print_r($c);
+
+$c = totals($jolts);
+print_r($c);
+